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Initial implementation of MD5 checksums for session and single data files.

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To be activated by macro Libisofs_with_checksumS.
New AAIP attributes "isfs.ca" and "isofs.cx".
New API calls iso_image_get_session_md5() and iso_file_get_md5().
This commit is contained in:
Thomas Schmitt 2009-08-10 13:56:06 +02:00
parent 55690756ae
commit b5f4a66c59
15 changed files with 1349 additions and 40 deletions
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108
doc/susp_aaip_isofs_names.txt
View File

@ -12,6 +12,93 @@ specification of AAIP :
-------------------------------------------------------------------------------
Name:
isofs.ca
Purpose:
Records the range of checksummed image data (START, END), the number
of checksum items (COUNT), the number of bytes in a single checksum item
(SIZE), and the name of the checksum algorithm (CHECKSUM_TYPE).
END is also the block address of the start of the checksum recording
area in the image.
See also isofs.cx .
Format of Value:
START_LEN | START_BYTES | END_LEN | END_BYTES |
COUNT_LEN | COUNT_BYTES | SIZE_LEN | SIZE_BYTES | CHECKSUM_TYPE
Each number is encoded as _LEN byte and _BYTES value string.
The _LEN fields comply to ISO 9660 Format section 7.1.1.
The byte strings START_BYTES, END_BYTES, COUNT_BYTES, SIZE_BYTES begin
with the most significant byte. Leading zero bytes are allowed.
CHECKSUM_TYPE consists of the bytes after
START_LEN + END_LEN + COUNT_LEN + SIZE_LEN + 4.
It shall be a string of printable characters without terminating 0-byte.
Type names shall be registered here.
For now there is:
"MD5" 128 bit message digest, see RFC 1321, see man md5sum
Example:
LBA range 32 to 1000000 , 520 checksums recorded, MD5
{ 1, 32,
3, 15, 66, 64,
2, 2, 8,
1, 16,
'M', 'D', '5' }
or
{ 4, 0, 0, 0, 32,
4, 0, 15, 66, 64,
4, 0, 0, 2, 8,
1, 16,
'M', 'D', '5' }
Registered:
16 Jul 2009 by Thomas Schmitt for libisofs.
-------------------------------------------------------------------------------
Name:
isofs.cs
Purpose:
Records the name of the character set that was used as output character
set when writing the RRIP name tree of the ISO 9660 image. It shall be
suitable as parameter for function iconv_open(3).
This attribute shall eventually be attached to the root directory entry
and be global for the whole image.
Format of Value:
Shall hold the character set name without terminating 0-byte.
Example:
{ 'I', 'S', 'O', '-', '8', '8', '5', '9' , '-', '1' }
Registered:
18 Mar 2009 by Thomas Schmitt for libisofs.
-------------------------------------------------------------------------------
Name:
isofs.cx
Purpose:
Records the index of the file's checksum in the checksum area at the
end of the image. The byte address of the checksum is
checksum_area_lba * 2048 + isofs.cx * checksum_size
Default checksum algorithm is MD5 with a size of 16 byte.
See also isofs.ca .
Format of Value:
A byte string which begins with the most significant byte.
Example:
Index 123456
{ 1, 226, 64 }
Registered:
16 Jul 2009 by Thomas Schmitt for libisofs.
-------------------------------------------------------------------------------
Name:
isofs.di
@ -34,27 +121,6 @@ Registered:
-------------------------------------------------------------------------------
Name:
isofs.cs
Purpose:
Records the name of the character set that was used as output character
set when writing the RRIP name tree of the ISO 9660 image. It shall be
suitable as parameter for function iconv_open(3).
This attribute shall eventually be attached to the root directory entry
and be global for the whole image.
Format of Value:
Shall hold the character set name without terminating 0-byte.
Example:
{ 'I', 'S', 'O', '-', '8', '8', '5', '9' , '-', '1' }
Registered:
18 Mar 2009 by Thomas Schmitt for libisofs.
-------------------------------------------------------------------------------
Name:
isofs.st

157
libisofs/ecma119.c
View File

@ -27,6 +27,10 @@
#include "util.h"
#include "system_area.h"
#ifdef Libisofs_with_checksumS
#include "md5.h"
#endif
#include <stdlib.h>
#include <time.h>
#include <string.h>
@ -57,6 +61,14 @@ void ecma119_image_free(Ecma119Image *t)
}
free(t->input_charset);
free(t->output_charset);
#ifdef Libisofs_with_checksumS
if (t->checksum_ctx != NULL) /* dispose checksum context */
libisofs_md5(&(t->checksum_ctx), NULL, 0, NULL, (1 << 15));
if (t->checksum_buffer != NULL)
free(t->checksum_buffer);
#endif
free(t->writers);
free(t);
}
@ -294,7 +306,7 @@ void write_one_dir_record(Ecma119Image *t, Ecma119Node *node, int file_id,
rec->len_dr[0] = len_dr + (info != NULL ? info->suf_len : 0);
iso_bb(rec->block, block, 4);
iso_bb(rec->length, len, 4);
if(t->dir_rec_mtime) {
if (t->dir_rec_mtime) {
iso= node->node;
iso_datetime_7(rec->recording_time,
t->replace_timestamps ? t->timestamp : iso->mtime,
@ -860,6 +872,79 @@ void *write_function(void *arg)
pthread_exit(NULL);
}
#ifdef Libisofs_with_checksumS
static
int checksum_prepare_image(IsoImage *src, int flag)
{
int ret;
/* Set provisory value of isofs.ca with
4 byte LBA, 4 byte count, size 16, name MD5 */
ret = iso_root_set_isofsca((IsoNode *) src->root, 0, 0, 0, 16, "MD5", 0);
if (ret < 0)
return ret;
return ISO_SUCCESS;
}
/*
@flag bit0= recursion
*/
static
int checksum_prepare_nodes(IsoImage *img, IsoNode *node, int flag)
{
IsoNode *pos;
IsoFile *file;
int ret, i;
size_t value_length;
unsigned int idx = 0;
char *value;
void *xipt = NULL;
if (node->type == LIBISO_FILE) {
file = (IsoFile *) node;
if (file->from_old_session) {
/* Save eventual MD5 data of files from old image */
value= NULL;
ret = iso_node_lookup_attr(node, "isofs.cx", &value_length,
&value, 0);
if (ret == 1 && value_length == 4) {
for (i = 0; i < 4; i++)
idx = (idx << 8) | ((unsigned char *) value)[i];
if (idx > 0 && idx < 0x8000000) {
/* xipt is an int disguised as void pointer */
for (i = 0; i < 4; i++)
((char *) &xipt)[i] = value[i];
ret = iso_node_add_xinfo(node, checksum_xinfo_func,
xipt);
if (ret < 0)
return ret;
}
}
if (value != NULL)
free(value);
}
/* Equip all nodes with provisory isofs.cx numbers: 4 byte, all 0. */
ret = iso_file_set_isofscx(file, (unsigned int) 0, 0);
if (ret < 0)
return ret;
} else if (node->type == LIBISO_DIR) {
for (pos = ((IsoDir *) node)->children; pos != NULL; pos = pos->next) {
ret = checksum_prepare_nodes(img, pos, 1);
if (ret < 0)
return ret;
}
}
return ISO_SUCCESS;
}
#endif /* Libisofs_with_checksumS */
static
int ecma119_image_new(IsoImage *src, IsoWriteOpts *opts, Ecma119Image **img)
{
@ -951,6 +1036,18 @@ int ecma119_image_new(IsoImage *src, IsoWriteOpts *opts, Ecma119Image **img)
return ISO_OUT_OF_MEM;
}
#ifdef Libisofs_with_checksumS
/* >>> need an IsoWriteOpts component to control this */;
target->md5_checksums = 1;
target->checksum_idx_counter = 0;
target->checksum_ctx = NULL;
target->checksum_counter = 0;
target->checksum_buffer = NULL;
#endif
/*
* 2. Based on those options, create needed writers: iso, joliet...
* Each writer inits its structures and stores needed info into
@ -974,6 +1071,25 @@ int ecma119_image_new(IsoImage *src, IsoWriteOpts *opts, Ecma119Image **img)
nwriters++;
}
#ifdef Libisofs_with_checksumS
if (target->md5_checksums) {
nwriters++;
ret = checksum_prepare_image(src, 0);
if (ret < 0)
return ret;
if (target->appendable) {
ret = checksum_prepare_nodes(src, (IsoNode *) src->root, 0);
if (ret < 0)
return ret;
}
target->checksum_idx_counter = 0;
}
#endif /* Libisofs_with_checksumS */
target->writers = malloc(nwriters * sizeof(void*));
if (target->writers == NULL) {
iso_image_unref(src);
@ -1019,7 +1135,7 @@ int ecma119_image_new(IsoImage *src, IsoWriteOpts *opts, Ecma119Image **img)
/*
* Create the writer for possible padding to ensure that in case of image
* growing we can safety overwrite the first 64 KiB of image.
* growing we can safely overwrite the first 64 KiB of image.
*/
ret = pad_writer_create(target);
if (ret < 0) {
@ -1033,6 +1149,20 @@ int ecma119_image_new(IsoImage *src, IsoWriteOpts *opts, Ecma119Image **img)
}
file_src_writer_index = target->nwriters - 1;
#ifdef Libisofs_with_checksumS
/* ??? Is it safe to add a writer after the content writer ? */
if (target->md5_checksums) {
ret = checksum_writer_create(target);
if (ret < 0)
goto target_cleanup;
}
#endif /* Libisofs_with_checksumS */
/*
* 3.
* Call compute_data_blocks() in each Writer.
@ -1140,7 +1270,15 @@ int ecma119_image_new(IsoImage *src, IsoWriteOpts *opts, Ecma119Image **img)
target->vol_space_size = target->curblock - target->ms_block;
target->total_size = (off_t) target->vol_space_size * BLOCK_SIZE;
/* 4. Create and start writting thread */
/* 4. Create and start writing thread */
#ifdef Libisofs_with_checksumS
/* After any fake writes are done: Initialize image checksum context */
ret = libisofs_md5(&(target->checksum_ctx), NULL, 0, NULL, 1);
if (ret < 0)
return ret;
#endif /* Libisofs_with_checksumS */
/* ensure the thread is created joinable */
pthread_attr_init(&(target->th_attr));
@ -1306,6 +1444,17 @@ int iso_write(Ecma119Image *target, void *buf, size_t count)
return ISO_CANCELED;
}
#ifdef Libisofs_with_checksumS
if (target->checksum_ctx != NULL) {
/* Add to image checksum */
target->checksum_counter += count;
libisofs_md5(&(target->checksum_ctx), (char *) buf, (int) count,
NULL, 0);
}
#endif /* Libisofs_with_checksumS */
/* total size is 0 when writing the overwrite buffer */
if (ret > 0 && (target->total_size != (off_t) 0)){
unsigned int kbw, kbt;
@ -1710,7 +1859,7 @@ int iso_write_opts_set_fifo_size(IsoWriteOpts *opts, size_t fifo_size)
int iso_write_opts_get_data_start(IsoWriteOpts *opts, uint32_t *data_start,
int flag)
{
if(opts->data_start_lba == 0)
if (opts->data_start_lba == 0)
return ISO_ERROR;
*data_start = opts->data_start_lba;
return ISO_SUCCESS;

16
libisofs/ecma119.h
View File

@ -312,6 +312,12 @@ struct ecma119_image
/* Store in ECMA-119 timestamp mtime of source */
unsigned int dir_rec_mtime :1;
#ifdef Libisofs_with_checksumS
unsigned int md5_checksums :1;
#endif /* Libisofs_with_checksumS */
/*
* Mode replace. If one of these flags is set, the correspodent values are
* replaced with values below.
@ -421,6 +427,16 @@ struct ecma119_image
/* tree of files sources */
IsoRBTree *files;
#ifdef Libisofs_with_checksumS
unsigned int checksum_idx_counter;
void *checksum_ctx;
off_t checksum_counter;
char image_md5[16];
char *checksum_buffer;
#endif /* Libisofs_with_checksumS */
/* Buffer for communication between burn_source and writer thread */
IsoRingBuffer *buffer;

113
libisofs/filesrc.c
View File

@ -14,6 +14,10 @@
#include "image.h"
#include "stream.h"
#ifdef Libisofs_with_checksumS
#include "md5.h"
#endif /* Libisofs_with_checksumS */
#include <stdlib.h>
#include <string.h>
#include <limits.h>
@ -44,6 +48,10 @@ int iso_file_src_create(Ecma119Image *img, IsoFile *file, IsoFileSrc **src)
dev_t dev_id;
ino_t ino_id;
#ifdef Libisofs_with_checksumS
int cret;
#endif
if (img == NULL || file == NULL || src == NULL) {
return ISO_NULL_POINTER;
}
@ -88,11 +96,42 @@ int iso_file_src_create(Ecma119Image *img, IsoFile *file, IsoFileSrc **src)
/* insert the filesrc in the tree */
ret = iso_rbtree_insert(img->files, fsrc, (void**)src);
if (ret <= 0) {
#ifdef Libisofs_with_checksumS
if (ret == 0) {
/* Duplicate file source was mapped to previously registered source
*/
cret = iso_file_set_isofscx(file, (*src)->checksum_index, 0);
if (cret < 0)
ret = cret;
}
#endif /* Libisofs_with_checksumS */
free(fsrc->sections);
free(fsrc);
return ret;
}
iso_stream_ref(fsrc->stream);
#ifdef Libisofs_with_checksumS
if(img->md5_checksums) {
img->checksum_idx_counter++;
if (img->checksum_idx_counter < 0x80000000) {
fsrc->checksum_index= img->checksum_idx_counter;
} else {
fsrc->checksum_index= 0;
img->checksum_idx_counter= 0x80000000; /* keep from rolling over */
}
cret = iso_file_set_isofscx(file, (*src)->checksum_index, 0);
if (cret < 0)
return cret;
}
#endif /* Libisofs_with_checksumS */
return ISO_SUCCESS;
}
@ -276,6 +315,14 @@ int filesrc_writer_write_data(IsoImageWriter *writer)
IsoFileSrc **filelist;
char name[PATH_MAX];
char buffer[BLOCK_SIZE];
off_t file_size;
uint32_t nblocks;
#ifdef Libisofs_with_checksumS
void *ctx= NULL;
char md5[16];
#endif
if (writer == NULL) {
return ISO_ASSERT_FAILURE;
@ -288,8 +335,10 @@ int filesrc_writer_write_data(IsoImageWriter *writer)
i = 0;
while ((file = filelist[i++]) != NULL) {
file_size = iso_file_src_get_size(file);
nblocks = DIV_UP(file_size, BLOCK_SIZE);
uint32_t nblocks = DIV_UP(iso_file_src_get_size(file), BLOCK_SIZE);
/* >>> Eventually obtain an MD5 of content by a first read pass */;
res = filesrc_open(file);
iso_stream_get_file_name(file->stream, name);
@ -329,6 +378,18 @@ int filesrc_writer_write_data(IsoImageWriter *writer)
}
#endif
#ifdef Libisofs_with_checksumS
if (file->checksum_index > 0) {
/* initialize file checksum */
res = libisofs_md5(&ctx, NULL, 0, md5, 1);
if (res <= 0)
file->checksum_index = 0;
}
#endif /* Libisofs_with_checksumS */
/* write file contents to image */
for (b = 0; b < nblocks; ++b) {
int wres;
@ -343,6 +404,21 @@ int filesrc_writer_write_data(IsoImageWriter *writer)
filesrc_close(file);
return wres;
}
#ifdef Libisofs_with_checksumS
if (file->checksum_index > 0) {
/* Add to file checksum */
res = file_size - b * BLOCK_SIZE;
if (res > BLOCK_SIZE)
res = BLOCK_SIZE;
res = libisofs_md5(&ctx, buffer, res, md5, 0);
if (res <= 0)
file->checksum_index = 0;
}
#endif /* Libisofs_with_checksumS */
}
filesrc_close(file);
@ -374,8 +450,41 @@ int filesrc_writer_write_data(IsoImageWriter *writer)
/* ko, writer error, we need to go out! */
return res;
}
#ifdef Libisofs_with_checksumS
if (file->checksum_index > 0) {
/* Add to file checksum */
res = file_size - b * BLOCK_SIZE;
if (res > BLOCK_SIZE)
res = BLOCK_SIZE;
res = libisofs_md5(&ctx, buffer, res, md5, 0);
if (res <= 0)
file->checksum_index = 0;
}
#endif /* Libisofs_with_checksumS */
}
}
#ifdef Libisofs_with_checksumS
if (file->checksum_index > 0) {
/* Obtain checksum and dispose checksum context */
res = libisofs_md5(&ctx, buffer, 0, md5, 2 | (1 << 15));
if (res <= 0)
file->checksum_index = 0;
/* >>> Eventually compare with MD5 of first read pass
and issue error if mismatch */;
/* Write md5 into checksum buffer at file->checksum_index */
memcpy(t->checksum_buffer + 16 * file->checksum_index, md5, 16);
}
#endif /* Libisofs_with_checksumS */
}
return ISO_SUCCESS;
@ -395,7 +504,7 @@ int iso_file_src_writer_create(Ecma119Image *target)
writer = malloc(sizeof(IsoImageWriter));
if (writer == NULL) {
return ISO_ASSERT_FAILURE;
return ISO_OUT_OF_MEM;
}
writer->compute_data_blocks = filesrc_writer_compute_data_blocks;

9
libisofs/filesrc.h
View File

@ -18,6 +18,13 @@ struct Iso_File_Src
{
unsigned int prev_img :1; /**< if the file comes from a previous image */
#ifdef Libisofs_with_checksumS
unsigned int checksum_index :31;
#endif /* Libisofs_with_checksumS */
/** File Sections of the file in the image */
struct iso_file_section *sections;
int nsections;
@ -43,7 +50,7 @@ int iso_file_src_cmp(const void *n1, const void *n2);
* @param src
* Will be filled with a pointer to the IsoFileSrc
* @return
* 1 on success, < 0 on error
* 1 if new object was created, 0 if object existed, < 0 on error
*/
int iso_file_src_create(Ecma119Image *img, IsoFile *file, IsoFileSrc **src);

71
libisofs/fs_image.c
View File

@ -2935,6 +2935,18 @@ int iso_image_import(IsoImage *image, IsoDataSource *src,
_ImageFsData *data;
struct el_torito_boot_catalog *oldbootcat;
#ifdef Libisofs_with_checksumS
int i;
uint32_t old_checksum_start_lba;
uint32_t old_checksum_end_lba;
uint32_t old_checksum_idx_count;
char *old_checksum_array = NULL;
char checksum_type[81];
uint32_t checksum_size;
size_t size;
uint8_t *rpt;
#endif
if (image == NULL || src == NULL || opts == NULL) {
return ISO_NULL_POINTER;
}
@ -2956,9 +2968,16 @@ int iso_image_import(IsoImage *image, IsoDataSource *src,
blback = image->builder;
oldroot = image->root;
oldbootcat = image->bootcat; /* could be NULL */
image->bootcat = NULL;
#ifdef Libisofs_with_checksumS
old_checksum_start_lba = image->checksum_start_lba;
old_checksum_end_lba = image->checksum_end_lba;
old_checksum_idx_count = image->checksum_idx_count;
old_checksum_array = image->checksum_array;
image->checksum_array = NULL;
#endif
/* create new builder */
ret = iso_image_builder_new(blback, &image->builder);
if (ret < 0) {
@ -3119,7 +3138,7 @@ int iso_image_import(IsoImage *image, IsoDataSource *src,
*features = malloc(sizeof(IsoReadImageFeatures));
if (*features == NULL) {
ret = ISO_OUT_OF_MEM;
goto import_cleanup;
goto import_revert;
}
(*features)->hasJoliet = data->joliet;
(*features)->hasRR = data->rr_version != 0;
@ -3128,6 +3147,39 @@ int iso_image_import(IsoImage *image, IsoDataSource *src,
(*features)->size = data->nblocks;
}
#ifdef Libisofs_with_checksumS
/* Read checksum buffer */
/* >>> needs to be controlled by iso_read_opts */;
ret = iso_root_get_isofsca((IsoNode *) image->root,
&(image->checksum_start_lba),
&(image->checksum_end_lba),
&(image->checksum_idx_count),
&checksum_size, checksum_type, 0);
if (ret > 0)
if (checksum_size != 16 || strcmp(checksum_type, "MD5") != 0)
ret = 0;
if (ret > 0) {
size = image->checksum_idx_count / 128 + 1;
image->checksum_array = calloc(size, 2048);
if (image->checksum_array == NULL) {
ret = ISO_OUT_OF_MEM;
goto import_revert;
}
/* Load from image->checksum_end_lba */;
for (i = 0; i < size; i++) {
rpt = (uint8_t *) (image->checksum_array + i * 2048);
ret = src->read_block(src, image->checksum_end_lba + i, rpt);
if (ret <= 0)
goto import_revert;
}
}
#endif /* Libisofs_with_checksumS */
ret = ISO_SUCCESS;
goto import_cleanup;
@ -3136,9 +3188,16 @@ int iso_image_import(IsoImage *image, IsoDataSource *src,
iso_node_unref((IsoNode*)image->root);
el_torito_boot_catalog_free(image->bootcat);
image->root = oldroot;
image->fs = fsback;
image->bootcat = oldbootcat;
#ifdef Libisofs_with_checksumS
old_checksum_start_lba = image->checksum_start_lba;
old_checksum_end_lba = image->checksum_end_lba;
old_checksum_idx_count = image->checksum_idx_count;
image->checksum_array = old_checksum_array;
old_checksum_array = NULL;
#endif
import_cleanup:;
/* recover backed fs and builder */
@ -3149,6 +3208,12 @@ int iso_image_import(IsoImage *image, IsoDataSource *src,
fs->close(fs);
iso_filesystem_unref(fs);
#ifdef Libisofs_with_checksumS
if (old_checksum_array != NULL)
free(old_checksum_array);
#endif
return ret;
}

30
libisofs/image.c
View File

@ -78,6 +78,14 @@ int iso_image_new(const char *name, IsoImage **image)
img->inode_counter = 0;
img->used_inodes = NULL;
img->used_inodes_start = 0;
#ifdef Libisofs_with_checksumS
img->checksum_start_lba = 0;
img->checksum_end_lba = 0;
img->checksum_idx_count = 0;
img->checksum_array = NULL;
#endif
*image = img;
return ISO_SUCCESS;
}
@ -529,3 +537,25 @@ ex:;
return ret;
}
/* API */
int iso_image_get_session_md5(IsoImage *image, uint32_t *start_lba,
uint32_t *end_lba, char md5[16], int flag)
{
#ifdef Libisofs_with_checksumS
if (image->checksum_array == NULL || image->checksum_idx_count < 1)
return 0;
*start_lba = image->checksum_start_lba;
*end_lba = image->checksum_end_lba;
memcpy(md5, image->checksum_array, 16);
return ISO_SUCCESS;
#else
return 0;
#endif /* ! Libisofs_with_checksumS */
}

16
libisofs/image.h
View File

@ -148,6 +148,22 @@ struct Iso_Image
uint8_t *used_inodes;
ino_t used_inodes_start;
#ifdef Libisofs_with_checksumS
/**
* Array of MD5 checksums as announced by xattr "isofs.ca" of the
* root node. Array element 0 contains an overall image checksum for the
* block range checksum_start_lba,checksum_end_lba. Element size is
* 16 bytes. IsoFile objects in the image may have xattr "isofs.cx"
* which gives their index in checksum_array.
*/
uint32_t checksum_start_lba;
uint32_t checksum_end_lba;
uint32_t checksum_idx_count;
char *checksum_array;
#endif /* Libisofs_with_checksumS */
};

76
libisofs/libisofs.h
View File

@ -4442,7 +4442,11 @@ int iso_node_lookup_attr(IsoNode *node, char *name,
* bit0= Do not maintain eventual existing ACL of the node.
* Set eventual new ACL from value of empty name.
* bit1= Do not clear the existing attribute list but merge it with
* the list given by this call
* the list given by this call.
* The given values override the values of their eventually existing
* names. If no xattr with a given name exists, then it will be
* added as new xattr. So this bit can be used to set a single
* xattr without inquiring any other xattr of the node.
* bit2= Delete the attributes with the given names
* bit3= Allow to affect non-user attributes.
* I.e. those with a non-empty name which does not begin by "user."
@ -4953,6 +4957,57 @@ int iso_file_add_gzip_filter(IsoFile *file, int flag);
int iso_gzip_get_refcounts(off_t *gzip_count, off_t *gunzip_count, int flag);
/* ---------------------------- MD5 Checksums --------------------------- */
/**
* Eventually obtain the recorded MD5 checksum of the session which was
* loaded as ISO image. Such a checksum may be stored together with others
* in a contiguous array at the end of the ISO image. The session checksum
* covers the data blocks from address start_lba to address end_lba - 1.
* It does not cover the recorded array of md5 checksums.
* Layout, size, and position of the checksum array is recorded in the xattr
* "isofs.ca" of the session root node.
* @param image
* The image to inquire
* @param start_lba
* Eventually returns the first block address covered by md5
* @param start_lba
* Eventually returns the first block address not covered by md5 any more
* @param md5
* Eventually returns 16 byte of MD5 checksum
* @param flag
* Bitfield for control purposes, unused yet, submit 0
* @return
* 1= md5 found , 0= no md5 available , <0 indicates error
*
* @since 0.6.22
*/
int iso_image_get_session_md5(IsoImage *image, uint32_t *start_lba,
uint32_t *end_lba, char md5[16], int flag);
/**
* Eventually obtain the recorded MD5 checksum of a data file from the loaded
* ISO image. Such a checksum may be stored with others in a contiguous
* array at the end of the ISO image. The data file eventually has an xattr
* "isofs.cx" which gives the index in that array.
* @param image
* The image from which file stems.
* @param file
* The file object to inquire
* @param md5
* Eventually returns 16 byte of MD5 checksum
* @param flag
* Bitfield for control purposes, unused yet, submit 0
* @return
* 1= md5 found , 0= no md5 available , <0 indicates error
*
* @since 0.6.22
*/
int iso_file_get_md5(IsoImage *image, IsoFile *file, char md5[16], int flag);
/************ Error codes and return values for libisofs ********************/
/** successfully execution */
@ -5412,12 +5467,9 @@ struct burn_source {
/* currently none being tested */
/* ---------------------------- Improvements --------------------------- */
/* currently none being tested */
/* ---------------------------- Experiments ---------------------------- */
/* Hardlinks : During image generation accompany the tree of IsoFileSrc
by a sorted array of Ecma119Node.
The sorting order shall bring together candidates for being
@ -5439,7 +5491,10 @@ struct burn_source {
#define Libisofs_hardlink_prooF yes
/* Experiment: Ignore PX inode numbers,
/* ---------------------------- Experiments ---------------------------- */
/* <<< on its way out
Experiment: Ignore PX inode numbers,
have boot image inode number counted by fs_give_ino_number()
Overridden if Libisofs_hardlink_prooF is defined.
@ -5455,5 +5510,14 @@ struct burn_source {
*/
/* Experiment: During image writing equip IsoFile objects with MD5 checksums
and compute an overall checksum of the image. Store them in
a separate checksum block area after the data area of the
image.
ENABLE ONLY FOR DEVELOPMENT TESTS !
#define Libisofs_with_checksumS yes
*/
#endif /*LIBISO_LIBISOFS_H_*/

514
libisofs/md5.c Normal file
View File

@ -0,0 +1,514 @@
/*
* Copyright (c) 2009 Thomas Schmitt
*
* This file is part of the libisofs project; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation. See COPYING file for details.
*/
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include "writer.h"
#include "messages.h"
#include "ecma119.h"
#include "image.h"
#include "md5.h"
/* This code is derived from RFC 1321 and implements computation of the
"RSA Data Security, Inc. MD5 Message-Digest Algorithm" */
#define Libisofs_md5_S11 7
#define Libisofs_md5_S12 12
#define Libisofs_md5_S13 17
#define Libisofs_md5_S14 22
#define Libisofs_md5_S21 5
#define Libisofs_md5_S22 9
#define Libisofs_md5_S23 14
#define Libisofs_md5_S24 20
#define Libisofs_md5_S31 4
#define Libisofs_md5_S32 11
#define Libisofs_md5_S33 16
#define Libisofs_md5_S34 23
#define Libisofs_md5_S41 6
#define Libisofs_md5_S42 10
#define Libisofs_md5_S43 15
#define Libisofs_md5_S44 21
/* F, G, H and I are basic MD5 functions.
*/
#define Libisofs_md5_F(x, y, z) (((x) & (y)) | ((~x) & (z)))
#define Libisofs_md5_G(x, y, z) (((x) & (z)) | ((y) & (~z)))
#define Libisofs_md5_H(x, y, z) ((x) ^ (y) ^ (z))
#define Libisofs_md5_I(x, y, z) ((y) ^ ((x) | (~z)))
/* ROTATE_LEFT rotates x left n bits.
*/
#define Libisofs_md5_ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
/* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
Rotation is separate from addition to prevent recomputation.
*/
#define Libisofs_md5_FF(a, b, c, d, x, s, ac) { \
(a) += Libisofs_md5_F ((b), (c), (d)) + (x) + (uint32_t)(ac); \
(a) = Libisofs_md5_ROTATE_LEFT ((a), (s)); \
(a) += (b); \
}
#define Libisofs_md5_GG(a, b, c, d, x, s, ac) { \
(a) += Libisofs_md5_G ((b), (c), (d)) + (x) + (uint32_t)(ac); \
(a) = Libisofs_md5_ROTATE_LEFT ((a), (s)); \
(a) += (b); \
}
#define Libisofs_md5_HH(a, b, c, d, x, s, ac) { \
(a) += Libisofs_md5_H ((b), (c), (d)) + (x) + (uint32_t)(ac); \
(a) = Libisofs_md5_ROTATE_LEFT ((a), (s)); \
(a) += (b); \
}
#define Libisofs_md5_II(a, b, c, d, x, s, ac) { \
(a) += Libisofs_md5_I ((b), (c), (d)) + (x) + (uint32_t)(ac); \
(a) = Libisofs_md5_ROTATE_LEFT ((a), (s)); \
(a) += (b); \
}
/* MD5 context. */
struct _libisofs_md5_ctx {
uint32_t state[4]; /* state (ABCD) */
uint32_t count[2]; /* number of bits, modulo 2^64 (lsb first) */
unsigned char buffer[64]; /* input buffer */
};
typedef struct _libisofs_md5_ctx libisofs_md5_ctx;
/* MD5 basic transformation. Transforms state based on block.
*/
static int md5__transform (uint32_t state[4], unsigned char block[64])
{
uint32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
unsigned int i, j;
for (i = 0, j = 0; j < 64; i++, j += 4)
x[i] = ((uint32_t)block[j]) | (((uint32_t)block[j+1]) << 8) |
(((uint32_t)block[j+2]) << 16) | (((uint32_t)block[j+3]) << 24);
/* Round 1 */
Libisofs_md5_FF (a, b, c, d, x[ 0], Libisofs_md5_S11, 0xd76aa478); /* 1 */
Libisofs_md5_FF (d, a, b, c, x[ 1], Libisofs_md5_S12, 0xe8c7b756); /* 2 */
Libisofs_md5_FF (c, d, a, b, x[ 2], Libisofs_md5_S13, 0x242070db); /* 3 */
Libisofs_md5_FF (b, c, d, a, x[ 3], Libisofs_md5_S14, 0xc1bdceee); /* 4 */
Libisofs_md5_FF (a, b, c, d, x[ 4], Libisofs_md5_S11, 0xf57c0faf); /* 5 */
Libisofs_md5_FF (d, a, b, c, x[ 5], Libisofs_md5_S12, 0x4787c62a); /* 6 */
Libisofs_md5_FF (c, d, a, b, x[ 6], Libisofs_md5_S13, 0xa8304613); /* 7 */
Libisofs_md5_FF (b, c, d, a, x[ 7], Libisofs_md5_S14, 0xfd469501); /* 8 */
Libisofs_md5_FF (a, b, c, d, x[ 8], Libisofs_md5_S11, 0x698098d8); /* 9 */
Libisofs_md5_FF (d, a, b, c, x[ 9], Libisofs_md5_S12, 0x8b44f7af); /* 10 */
Libisofs_md5_FF (c, d, a, b, x[10], Libisofs_md5_S13, 0xffff5bb1); /* 11 */
Libisofs_md5_FF (b, c, d, a, x[11], Libisofs_md5_S14, 0x895cd7be); /* 12 */
Libisofs_md5_FF (a, b, c, d, x[12], Libisofs_md5_S11, 0x6b901122); /* 13 */
Libisofs_md5_FF (d, a, b, c, x[13], Libisofs_md5_S12, 0xfd987193); /* 14 */
Libisofs_md5_FF (c, d, a, b, x[14], Libisofs_md5_S13, 0xa679438e); /* 15 */
Libisofs_md5_FF (b, c, d, a, x[15], Libisofs_md5_S14, 0x49b40821); /* 16 */
/* Round 2 */
Libisofs_md5_GG (a, b, c, d, x[ 1], Libisofs_md5_S21, 0xf61e2562); /* 17 */
Libisofs_md5_GG (d, a, b, c, x[ 6], Libisofs_md5_S22, 0xc040b340); /* 18 */
Libisofs_md5_GG (c, d, a, b, x[11], Libisofs_md5_S23, 0x265e5a51); /* 19 */
Libisofs_md5_GG (b, c, d, a, x[ 0], Libisofs_md5_S24, 0xe9b6c7aa); /* 20 */
Libisofs_md5_GG (a, b, c, d, x[ 5], Libisofs_md5_S21, 0xd62f105d); /* 21 */
Libisofs_md5_GG (d, a, b, c, x[10], Libisofs_md5_S22, 0x2441453); /* 22 */
Libisofs_md5_GG (c, d, a, b, x[15], Libisofs_md5_S23, 0xd8a1e681); /* 23 */
Libisofs_md5_GG (b, c, d, a, x[ 4], Libisofs_md5_S24, 0xe7d3fbc8); /* 24 */
Libisofs_md5_GG (a, b, c, d, x[ 9], Libisofs_md5_S21, 0x21e1cde6); /* 25 */
Libisofs_md5_GG (d, a, b, c, x[14], Libisofs_md5_S22, 0xc33707d6); /* 26 */
Libisofs_md5_GG (c, d, a, b, x[ 3], Libisofs_md5_S23, 0xf4d50d87); /* 27 */
Libisofs_md5_GG (b, c, d, a, x[ 8], Libisofs_md5_S24, 0x455a14ed); /* 28 */
Libisofs_md5_GG (a, b, c, d, x[13], Libisofs_md5_S21, 0xa9e3e905); /* 29 */
Libisofs_md5_GG (d, a, b, c, x[ 2], Libisofs_md5_S22, 0xfcefa3f8); /* 30 */
Libisofs_md5_GG (c, d, a, b, x[ 7], Libisofs_md5_S23, 0x676f02d9); /* 31 */
Libisofs_md5_GG (b, c, d, a, x[12], Libisofs_md5_S24, 0x8d2a4c8a); /* 32 */
/* Round 3 */
Libisofs_md5_HH (a, b, c, d, x[ 5], Libisofs_md5_S31, 0xfffa3942); /* 33 */
Libisofs_md5_HH (d, a, b, c, x[ 8], Libisofs_md5_S32, 0x8771f681); /* 34 */
Libisofs_md5_HH (c, d, a, b, x[11], Libisofs_md5_S33, 0x6d9d6122); /* 35 */
Libisofs_md5_HH (b, c, d, a, x[14], Libisofs_md5_S34, 0xfde5380c); /* 36 */
Libisofs_md5_HH (a, b, c, d, x[ 1], Libisofs_md5_S31, 0xa4beea44); /* 37 */
Libisofs_md5_HH (d, a, b, c, x[ 4], Libisofs_md5_S32, 0x4bdecfa9); /* 38 */
Libisofs_md5_HH (c, d, a, b, x[ 7], Libisofs_md5_S33, 0xf6bb4b60); /* 39 */
Libisofs_md5_HH (b, c, d, a, x[10], Libisofs_md5_S34, 0xbebfbc70); /* 40 */
Libisofs_md5_HH (a, b, c, d, x[13], Libisofs_md5_S31, 0x289b7ec6); /* 41 */
Libisofs_md5_HH (d, a, b, c, x[ 0], Libisofs_md5_S32, 0xeaa127fa); /* 42 */
Libisofs_md5_HH (c, d, a, b, x[ 3], Libisofs_md5_S33, 0xd4ef3085); /* 43 */
Libisofs_md5_HH (b, c, d, a, x[ 6], Libisofs_md5_S34, 0x4881d05); /* 44 */
Libisofs_md5_HH (a, b, c, d, x[ 9], Libisofs_md5_S31, 0xd9d4d039); /* 45 */
Libisofs_md5_HH (d, a, b, c, x[12], Libisofs_md5_S32, 0xe6db99e5); /* 46 */
Libisofs_md5_HH (c, d, a, b, x[15], Libisofs_md5_S33, 0x1fa27cf8); /* 47 */
Libisofs_md5_HH (b, c, d, a, x[ 2], Libisofs_md5_S34, 0xc4ac5665); /* 48 */
/* Round 4 */
Libisofs_md5_II (a, b, c, d, x[ 0], Libisofs_md5_S41, 0xf4292244); /* 49 */
Libisofs_md5_II (d, a, b, c, x[ 7], Libisofs_md5_S42, 0x432aff97); /* 50 */
Libisofs_md5_II (c, d, a, b, x[14], Libisofs_md5_S43, 0xab9423a7); /* 51 */
Libisofs_md5_II (b, c, d, a, x[ 5], Libisofs_md5_S44, 0xfc93a039); /* 52 */
Libisofs_md5_II (a, b, c, d, x[12], Libisofs_md5_S41, 0x655b59c3); /* 53 */
Libisofs_md5_II (d, a, b, c, x[ 3], Libisofs_md5_S42, 0x8f0ccc92); /* 54 */
Libisofs_md5_II (c, d, a, b, x[10], Libisofs_md5_S43, 0xffeff47d); /* 55 */
Libisofs_md5_II (b, c, d, a, x[ 1], Libisofs_md5_S44, 0x85845dd1); /* 56 */
Libisofs_md5_II (a, b, c, d, x[ 8], Libisofs_md5_S41, 0x6fa87e4f); /* 57 */
Libisofs_md5_II (d, a, b, c, x[15], Libisofs_md5_S42, 0xfe2ce6e0); /* 58 */
Libisofs_md5_II (c, d, a, b, x[ 6], Libisofs_md5_S43, 0xa3014314); /* 59 */
Libisofs_md5_II (b, c, d, a, x[13], Libisofs_md5_S44, 0x4e0811a1); /* 60 */
Libisofs_md5_II (a, b, c, d, x[ 4], Libisofs_md5_S41, 0xf7537e82); /* 61 */
Libisofs_md5_II (d, a, b, c, x[11], Libisofs_md5_S42, 0xbd3af235); /* 62 */
Libisofs_md5_II (c, d, a, b, x[ 2], Libisofs_md5_S43, 0x2ad7d2bb); /* 63 */
Libisofs_md5_II (b, c, d, a, x[ 9], Libisofs_md5_S44, 0xeb86d391); /* 64 */
state[0] += a;
state[1] += b;
state[2] += c;
state[3] += d;
/* Zeroize sensitive information. */
memset ((char *) x, 0, sizeof (x));
return(1);
}
static int md5__encode(unsigned char *output, uint32_t *input,
unsigned int len)
{
unsigned int i, j;
for (i = 0, j = 0; j < len; i++, j += 4) {
output[j] = (unsigned char)(input[i] & 0xff);
output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
}
return(1);
}
static int md5_init(libisofs_md5_ctx *ctx, int flag)
{
ctx->count[0] = ctx->count[1] = 0;
/* Load magic initialization constants. */
ctx->state[0] = 0x67452301;
ctx->state[1] = 0xefcdab89;
ctx->state[2] = 0x98badcfe;
ctx->state[3] = 0x10325476;
return(1);
}
/* MD5 block update operation. Continues an MD5 message-digest
operation, processing another message block, and updating the
context.
*/
static int md5_update(libisofs_md5_ctx *ctx, unsigned char *data,
int datalen, int flag)
{
unsigned int i, index, partlen;
/* Compute number of bytes mod 64 */
index = (unsigned int)((ctx->count[0] >> 3) & 0x3F);
/* Update number of bits */
if ((ctx->count[0] += ((uint32_t) datalen << 3)) <
((uint32_t) datalen << 3))
ctx->count[1]++;
ctx->count[1] += ((uint32_t) datalen >> 29);
partlen = 64 - index;
/* Transform as many times as possible. */
if (datalen >= partlen) {
memcpy((char *) &ctx->buffer[index], (char *) data, partlen);
md5__transform(ctx->state, ctx->buffer);
for (i = partlen; i + 63 < datalen; i += 64)
md5__transform(ctx->state, &data[i]);
index = 0;
} else
i = 0;
/* Buffer remaining data */
memcpy((char *) &ctx->buffer[index], (char *) &data[i],datalen-i);
return(1);
}
static int md5_final(libisofs_md5_ctx *ctx, char result[16], int flag)
{
unsigned char bits[8], *respt;
unsigned int index, padlen;
static unsigned char PADDING[64] = {
0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};
/* Save number of bits */
md5__encode(bits, ctx->count, 8);
/* Pad out to 56 mod 64. */
index = (unsigned int)((ctx->count[0] >> 3) & 0x3f);
padlen = (index < 56) ? (56 - index) : (120 - index);
md5_update(ctx, PADDING, padlen,0);
/* Append length (before padding) */
md5_update(ctx, bits, 8,0);
/* Store state in result */
respt= (unsigned char *) result;
md5__encode(respt, ctx->state, 16);
/* Zeroize sensitive information. */
memset ((char *) ctx, 0, sizeof (*ctx));
return(1);
}
int libisofs_md5(void **ctx_in, char *data, int datalen,
char result[16], int flag)
/* *ctx has to be NULL or point to freeable memory */
/*
bit0= allocate and init *ctx
bit1= transfer ctx to result
bit2= with bit 0 : clone new *ctx from data
bit15= free *ctx
*/
{
unsigned char *datapt;
libisofs_md5_ctx **ctx;
ctx= (libisofs_md5_ctx **) ctx_in;
if(flag&1) {
if(*ctx!=NULL)
free((char *) *ctx);
*ctx= calloc(1, sizeof(libisofs_md5_ctx));
if(*ctx==NULL)
return(-1);
md5_init(*ctx,0);
if(flag&4)
memcpy((char *) *ctx,data,sizeof(libisofs_md5_ctx));
}
if(*ctx==NULL)
return(0);
if(datalen>0) {
datapt= (unsigned char *) data;
md5_update(*ctx, datapt, datalen, 0);
}
if(flag&2)
md5_final(*ctx, result, 0);
if(flag&(1<<15)) {
free((char *) *ctx);
*ctx= NULL;
}
return(1);
}
/* ----------------------------------------------------------------------- */
/* Function to identify and manage md5sum indice of the old image.
* data is supposed to be a 4 byte integer, bit 31 shall be 0,
* value 0 of this integer means that it is not a valid index.
*/
int checksum_xinfo_func(void *data, int flag)
{
/* data is an int disguised as pointer. It does not point to memory. */
return 1;
}
#ifdef Libisofs_with_checksumS
/*
@flag bit0= recursion
bit1= session will be appended to an existing image
*/
static
int checksum_copy_old_nodes(Ecma119Image *target, IsoNode *node, int flag)
{
IsoNode *pos;
IsoFile *file;
IsoImage *img;
int ret, i;
size_t value_length;
unsigned int idx = 0, old_idx = 0;
char *value = NULL;
void *xipt;
img = target->image;
if (img->checksum_array == NULL || target->checksum_buffer == NULL)
return 0;
if (node->type == LIBISO_FILE) {
file = (IsoFile *) node;
if (file->from_old_session) {
ret = iso_node_get_xinfo(node, checksum_xinfo_func, &xipt);
if (ret <= 0)
return ret;
/* xipt is an int disguised as void pointer */
old_idx = 0;
for (i = 0; i < 4; i++)
old_idx = (old_idx << 8) | ((unsigned char *) &xipt)[i];
if (old_idx == 0 || old_idx > img->checksum_idx_count - 1)
return 0;
ret = iso_node_lookup_attr(node, "isofs.cx", &value_length,
&value, 0);
if (ret == 1 && value_length == 4) {
for (i = 0; i < 4; i++)
idx = (idx << 8) | ((unsigned char *) value)[i];
if (idx > 0 && idx <= target->checksum_idx_counter) {
memcpy(target->checksum_buffer + 16 * idx,
img->checksum_array + 16 * old_idx, 16);
}
}
if (value != NULL)
free(value);
}
} else if (node->type == LIBISO_DIR) {
for (pos = ((IsoDir *) node)->children; pos != NULL; pos = pos->next) {
ret = checksum_copy_old_nodes(target, pos, 1);
if (ret < 0)
return ret;
}
}
return ISO_SUCCESS;
}
#endif /* Libisofs_with_checksumS */
static
int checksum_writer_compute_data_blocks(IsoImageWriter *writer)
{
#ifdef Libisofs_with_checksumS
size_t size;
Ecma119Image *t;
int ret;
unsigned int lba;
if (writer == NULL) {
return ISO_ASSERT_FAILURE;
}
t = writer->target;
lba = t->curblock; /* (t->curblock already contains t->ms_block) */
size = (t->checksum_idx_counter + 2) / 128 + 1;
t->curblock += size;
/* >>> ??? reserve extra block for stream detectable checksum */;
/* Allocate array of MD5 sums */
t->checksum_buffer = calloc(size, 2048);
if (t->checksum_buffer == NULL)
return ISO_OUT_OF_MEM;
/* Copy MD5 from nodes of old image into writer->data */
ret = checksum_copy_old_nodes(t, (IsoNode *) t->image->root, 0);
if (ret < 0)
return ret;
/* Record lba,count,size,cecksum_type in "isofs.ca" of root node */
ret = iso_root_set_isofsca((IsoNode *) t->image->root,
(unsigned int) t->ms_block, lba,
t->checksum_idx_counter + 2, 16, "MD5", 0);
if (ret < 0)
return ret;
#endif /* Libisofs_with_checksumS */
return ISO_SUCCESS;
}
static
int checksum_writer_write_vol_desc(IsoImageWriter *writer)
{
/* nothing needed */
return ISO_SUCCESS;
}
static
int checksum_writer_write_data(IsoImageWriter *writer)
{
#ifdef Libisofs_with_checksumS
int wres, res;
size_t i, size;
Ecma119Image *t;
if (writer == NULL) {
return ISO_ASSERT_FAILURE;
}
t = writer->target;
iso_msg_debug(t->image->id, "Writing Checksums...");
/* Write image checksum to index 0 */
/* >>> rather fork a result than killing t->checksum_ctx */;
res = libisofs_md5(&(t->checksum_ctx), NULL, 0, t->image_md5,
2 | (1 << 15));
if (res > 0)
memcpy(t->checksum_buffer + 0, t->image_md5, 16);
size = (t->checksum_idx_counter + 2) / 128 + 1;
/* >>> write overall checksum as index t->checksum_idx_counter + 1 */;
for (i = 0; i < size; i++) {
wres = iso_write(t, t->checksum_buffer + ((size_t) 2048) * i,
BLOCK_SIZE);
if (wres < 0)
return wres;
}
/* >>> write scdbackup checksum tag to an extra block */;
#endif /* Libisofs_with_checksumS */
return ISO_SUCCESS;
}
static
int checksum_writer_free_data(IsoImageWriter *writer)
{
/* nothing was allocated at writer->data */
return ISO_SUCCESS;
}
int checksum_writer_create(Ecma119Image *target)
{
IsoImageWriter *writer;
writer = malloc(sizeof(IsoImageWriter));
if (writer == NULL) {
return ISO_OUT_OF_MEM;
}
writer->compute_data_blocks = checksum_writer_compute_data_blocks;
writer->write_vol_desc = checksum_writer_write_vol_desc;
writer->write_data = checksum_writer_write_data;
writer->free_data = checksum_writer_free_data;
writer->data = NULL;
writer->target = target;
/* add this writer to image */
target->writers[target->nwriters++] = writer;
return ISO_SUCCESS;
}

53
libisofs/md5.h Normal file
View File

@ -0,0 +1,53 @@
/*
* Copyright (c) 2009 Thomas Schmitt
*
* This file is part of the libisofs project; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation. See COPYING file for details.
*/
#ifndef LIBISO_MD5_H_
#define LIBISO_MD5_H_
/** Compute a MD5 checksum from one or more calls of this function.
The first call has to be made with flag bit0 == 1. It may already submit
processing payload in data and datalen.
The last call has to be made with bit15 set. Normally bit1 will be set
too in order to receive the checksum before it gets disposed.
bit1 may only be set in the last call or together with bit2.
The combination of bit1 and bit2 may be used to get an intermediate
result without hampering an ongoing checksum computation.
@param ctx the checksum context which stores the state between calls.
It gets created with flag bit0 and disposed with bit15.
With flag bit0, *ctx has to be NULL or point to freeable
memory.
@param data the bytes to be checksummed
@param datalen the number of bytes in data
@param result returns the 16 bytes of checksum if called with bit1 set
@param flag bit0= allocate and init *ctx
bit1= transfer ctx to result
bit2= with bit 0 : clone new *ctx from data
bit15= free *ctx
*/
int libisofs_md5(void **ctx, char *data, int datalen,
char result[16], int flag);
/** Create a writer object for checksums and add it to the writer list of
the given Ecma119Image.
*/
int checksum_writer_create(Ecma119Image *target);
/* Function to identify and manage md5sum indice of the old image.
* data is supposed to be a 4 byte integer, bit 31 shall be 0,
* value 0 of this integer means that it is not a valid index.
*/
int checksum_xinfo_func(void *data, int flag);
#endif /* ! LIBISO_MD5_H_ */

136
libisofs/node.c
View File

@ -13,6 +13,7 @@
#include "stream.h"
#include "aaip_0_2.h"
#include "messages.h"
#include "util.h"
#include <stdlib.h>
@ -2575,3 +2576,138 @@ int iso_node_cmp_ino(IsoNode *n1, IsoNode *n2, int flag)
{
return iso_node_cmp_flag(n1, n2, 1);
}
int iso_file_set_isofscx(IsoFile *file, unsigned int checksum_index,
int flag)
{
static char *names = "isofs.cx";
static size_t value_lengths[1] = {4};
unsigned char value[4];
char *valuept;
int i, ret;
for(i = 0; i < 4; i++)
value[3 - i] = (checksum_index >> (8 * i)) & 0xff;
valuept= (char *) value;
ret = iso_node_set_attrs((IsoNode *) file, (size_t) 1,
&names, value_lengths, &valuept, 2 | 8);
return ret;
}
int iso_root_set_isofsca(IsoNode *node, uint32_t start_lba, uint32_t end_lba,
uint32_t count, uint32_t size, char *typetext,
int flag)
{
char buffer[5 + 5 + 5 + 2 + 81], *wpt = buffer, *valuept = buffer;
int result_len, ret;
static char *names = "isofs.ca";
static size_t value_lengths[1];
/* Set value of isofs.ca with
4 byte START, 4 byte END, 4 byte COUNT, SIZE = 16, MD5 */
iso_util_encode_len_bytes(start_lba, wpt, 4, &result_len, 0);
wpt += result_len;
iso_util_encode_len_bytes(end_lba, wpt, 4, &result_len, 0);
wpt += result_len;
iso_util_encode_len_bytes(count, wpt, 4, &result_len, 0);
wpt += result_len;
iso_util_encode_len_bytes(size, wpt, 1, &result_len, 0);
wpt += result_len;
strncpy(wpt, typetext, 80);
if (strlen(typetext) > 80)
wpt += 80;
else
wpt += strlen(typetext);
value_lengths[0] = wpt - buffer;
ret = iso_node_set_attrs(node, (size_t) 1,
&names, value_lengths, &valuept, 2 | 8);
return ret;
}
int iso_root_get_isofsca(IsoNode *node, uint32_t *start_lba, uint32_t *end_lba,
uint32_t *count, uint32_t *size, char typetext[81],
int flag)
{
int ret, len;
size_t value_len;
char *value = NULL, *rpt;
ret = iso_node_lookup_attr(node, "isofs.ca", &value_len, &value, 0);
if (ret <= 0)
goto ex;
/* Parse value of isofs.ca with
4 byte START, 4 byte END, 4 byte COUNT, SIZE = 16, MD5 */
rpt = value;
iso_util_decode_len_bytes(start_lba, rpt, &len,
value_len - (rpt - value), 0);
rpt += len + 1;
iso_util_decode_len_bytes(end_lba, rpt, &len,
value_len - (rpt - value), 0);
rpt += len + 1;
iso_util_decode_len_bytes(count, rpt, &len,
value_len - (rpt - value), 0);
rpt += len + 1;
iso_util_decode_len_bytes(size, rpt, &len,
value_len - (rpt - value), 0);
rpt += len + 1;
len = value_len - (rpt - value);
if (len > 80)
len = 80;
memcpy(typetext, rpt, len);
typetext[len] = 0;
ret= ISO_SUCCESS;
ex:;
if (value != NULL)
free(value);
return ret;
}
/* API */
int iso_file_get_md5(IsoImage *image, IsoFile *file, char md5[16], int flag)
{
#ifdef Libisofs_with_checksumS
int ret, i;
size_t value_len;
char *value = NULL;
uint32_t idx = 0;
if (image->checksum_array == NULL)
return 0;
ret = iso_node_lookup_attr((IsoNode *) file, "isofs.cx",
&value_len, &value, 0);
if (ret <= 0)
goto ex;
if (value_len > 4) {
ret = 0;
goto ex;
}
for (i = 0; i < value_len; i++)
idx = (idx << 8) | ((unsigned char *) value)[i];
if (idx == 0 || idx > image->checksum_idx_count - 1) {
/* (last index is not MD5 of a file) */
ret = 0;
goto ex;
}
memcpy(md5, image->checksum_array + ((size_t) 16) * ((size_t) idx), 16);
ret = ISO_SUCCESS;
ex:;
if (value != NULL)
free(value);
return ret;
#else
return 0;
#endif /* ! Libisofs_with_checksumS */
}

31
libisofs/node.h
View File

@ -24,7 +24,7 @@
/**
* The extended information is a way to attach additional information to each
* IsoNode. External applications may want to use this extension system to
* store application speficic information related to each node. On the other
* store application specific information related to each node. On the other
* side, libisofs may make use of this struct to attach information to nodes in
* some particular, uncommon, cases, without incrementing the size of the
* IsoNode struct.
@ -67,7 +67,7 @@ struct iso_extended_info {
struct Iso_Node
{
/*
* Initilized to 1, originally owned by user, until added to another node.
* Initialized to 1, originally owned by user, until added to another node.
* Then it is owned by the parent node, so the user must take his own ref
* if needed. With the exception of the creation functions, none of the
* other libisofs functions that return an IsoNode increment its
@ -451,4 +451,31 @@ int iso_node_set_ino(IsoNode *node, ino_t ino, int flag);
*/
int iso_node_cmp_flag(IsoNode *n1, IsoNode *n2, int flag);
/**
* Set the checksum index (typically comming from IsoFileSrc.checksum_index)
* of a regular file node. The index is encoded as xattr "isofs.cx" with
* four bytes of value.
*/
int iso_file_set_isofscx(IsoFile *file, unsigned int checksum_index,
int flag);
/**
* Set the checksum area description. node should be the root node.
* It is encoded as xattr "isofs.ca".
*/
int iso_root_set_isofsca(IsoNode *node, uint32_t start_lba, uint32_t end_lba,
uint32_t count, uint32_t size, char *typetext,
int flag);
/**
* Get the checksum area description. node should be the root node.
* It is encoded as xattr "isofs.ca".
*/
int iso_root_get_isofsca(IsoNode *node, uint32_t *start_lba, uint32_t *end_lba,
uint32_t *count, uint32_t *size, char typetext[81],
int flag);
#endif /*LIBISO_NODE_H_*/

39
libisofs/util.c
View File

@ -1489,3 +1489,42 @@ int iso_init_locale(int flag)
}
int iso_util_encode_len_bytes(uint32_t data, char *buffer, int data_len,
int *result_len, int flag)
{
uint32_t x;
int i, l;
char *wpt = buffer;
if (data_len <= 0) {
x = data;
for (i = 0; i < 4 && x != 0; i++)
x = x >> 8;
l = i;
if (l == 0)
l = 1;
} else
l = data_len;
*((unsigned char *) (wpt++)) = l;
for (i = 0; i < l; i++)
*((unsigned char *) (wpt++)) = data >> (8 * (l - i - 1));
*result_len = l + 1;
return ISO_SUCCESS;
}
int iso_util_decode_len_bytes(uint32_t *data, char *buffer, int *data_len,
int buffer_len, int flag)
{
int i;
*data = 0;
*data_len = ((unsigned char *) buffer)[0];
if (*data_len > buffer_len - 1)
*data_len = buffer_len - 1;
for (i = 1; i <= *data_len; i++)
*data = (*data << 8) | ((unsigned char *) buffer)[i];
return ISO_SUCCESS;
}

18
libisofs/util.h
View File

@ -440,4 +440,22 @@ void iso_htable_destroy(IsoHTable *table, hfree_data_t free_data);
*/
unsigned int iso_str_hash(const void *key);
/**
* Encode an integer as LEN,BYTES for being a component in certain AAIP
* attribute values.
*/
int iso_util_encode_len_bytes(uint32_t data, char *buffer, int data_len,
int *result_len, int flag);
/**
* Decode an integer as LEN,BYTES for being a component in certain AAIP
* attribute values.
* @param data returns the decoded value
* @param buffer contains the encoded value
* @param data_len returns the number of value bytes (without len byte)
* @param buffer_len tells the number of valid buffer bytes
*/
int iso_util_decode_len_bytes(uint32_t *data, char *buffer, int *data_len,
int buffer_len, int flag);
#endif /*LIBISO_UTIL_H_*/